here's an issue i just found using mencoder that could perhaps be handled better. when mencoder starts writing an avi file, it puts a dummy header at the beginning, with information to be filled in later after the encoding is complete. the dummy header is good enough that mplayer can play an incomplete file generated by mencoder, but not good enough for mplayer (or mencoder in stream copy mode) to be able to rebuild an index for seeking. i've looked at aviwrite.c a bit, and although i'm not terribly familiar with the avi header format, it looks like aviwrite_write_header is putting several negative numbers in the header the first time it's called, whereas it probably should put 0 or the largest number that fits to make things work better when playing incomplete files. perhaps there should be a separate function aviwrite_write_dummy_header or something to handle all that. i hope you don't think this is nitpicking -- it's not absolutely necessary, but it would be very helpful to be able to seek (using -idx) in the file before it's complete, to confirm that the quality is adequate and such before spending all the time to encode the whole thing. btw, as a wishlist item that's sort of related...think it would be feasible to support resuming prematurely terminated encoding with mencoder, presumably at the last successful keyframe? it might be necessary to save some extra status info, but it would be rather useful... rich